The long term aim of this proposal is to develop a non-surgical method(s) to control the progressive growth of Benign Prostatic Hyperplasia (BPH). The immediate goal is to test the hypothesis that this glandular hyperplasia is due to an induction by a rejuvenated periurethral stroma. We believe an understanding of stromal induction will facilitate the targeting of a preventive approach against BPH. The first task is to obtain evidence that a stromal inducer is involved in the development of BPH. A culture system utilizing three dimensional acinar/ductal structures that retain in vivo features has been developed and will be indispensable for assaying inductive activity. Two complementary co-culture approaches are planned. One approach will use stromal cells isolated from BPH nodules and the other will use intact periurethral stroma. Both stromas will be recombined with acinar/ductal structures and studied under defined in vitro conditions. Specifically, we want to isolate the paracrine factor(s) responsible for stromal induction. Induction is measured as epithelial growth, differentiation and morphogenesis. Specificity of response will be checked using appropriate control cells and tissues. Specific responses will be checked for known growth factors with a battery of purified growth factors and, neutralizing antibodies. If the activity appears to be novel, then stromal conditioned media will be checked for activity and subjected to a preliminary study of its molecular weight and general physicochemical properties. For purification, the production of active conditioned stromal medium will be scaled up, the conditioned medium concentrated by ultrafiltration and the activity purified by gel filtration, ion-exchange (FPLC) and reversed phase HPLC.